A Rare Case of Gastric Neuroendocrine Tumor in a Patient With Vitamin B12 Deficiency.

Vitamin B12 deficiency can result from gastric neuroendocrine tumors (GNETs), which are uncommon neoplasms frequently linked to hypergastrinemia and chronic atrophic gastritis. Here, we report the case of a 48-year-old vegetarian male from South India who presented with jaundice, fatigue, and gastrointestinal discomfort. He was diagnosed with macrocytic anemia, mild hepatomegaly, and significant vitamin B12 deficiency. An incidental upper gastrointestinal endoscopy revealed multiple gastric nodules, later confirmed as a well-differentiated GNET. The patient also had a high hepatitis B viral load. He was treated with vitamin B12 supplementation and underwent resection of the tumor followed by antiviral therapy for hepatitis B. Postoperative recovery was uneventful with improvements in anemia and liver function. This case emphasizes the importance of a multidisciplinary approach and thorough evaluation when addressing patients with vitamin B12 insufficiency, hepatitis B, and GNET.

Classification of Gastric Neuroendocrine Tumors and Associations With Survival.

BACKGROUND AND OBJECTIVES: Not all gastric neuroendocrine tumors (GNETs) may be classified into one of the three described clinicopathologic subtypes. The purpose of this study was to better characterize GNET subtypes and associated outcomes. METHODS: Patients treated for GNET at our institution (1995-2021) were identified. Pathologic specimens of tumors that could not be classified as type 1, 2, or 3 were further reviewed. GNETs were categorized as proton pump inhibitor (PPI)-associated based on changes in the background gastric mucosa consistent with PPI use. Distant metastasis at presentation (DM) and disease-specific survival (DSS) were evaluated. RESULTS: Among 246 patients, there were 164 (67%) type 1, 5 (2%) type 2, 52 (21%) type 3, and 18 (7%) PPI-associated GNETs. Seven (3%) tumors remained unclassified. DM was more frequent with type 3 GNETs (38%) than type 1 (1%), type 2 (20%), or PPI-associated tumors (11%, p < 0.001). Ten-year DSS rates were 100% for type 1, 53% (95% confidence interval [CI], 38%-75%) for type 3, and 80% (95% CI, 58%-100%) for PPI-associated tumors (p < 0.001). GNET subtype, race, and DM were independently associated with DSS. CONCLUSIONS: PPI-associated tumors may represent a distinct GNET subtype with intermediate outcomes. Other factors should also be considered in overall prognosis.

Robotically assisted total gastrectomy for lymphadenopathy after long-term follow-up for multiple type 1 gastric neuroendocrine tumor (NET): a case report.

BACKGROUND: Type 1 gastric neuroendrine tumor (NET) is usually associated with chronic atrophic gastritis and forms multiple lesions. While most cases of type 1 gastric NET are generally slowly growing, some develop regional lymph node metastases even after long-term dormancy. CASE PRESENTATION: A 73-year-old male patient with a 32-year history of multiple gastric NET was being followed-up at the study center after endoscopic submucosal dissection (ESD) of a large gastric NET. A blood examination revealed high serum gastrin (> 3000 pg/ml). An endoscopic examination found atrophic mucosa and multiple, elevated lesions in the upper to lower stomach body. Computed tomography (CT) revealed regional lymphadenopathy in the greater omentum along the gastroepiploic artery. Robotically assisted total gastrectomy was performed with D2 lymphadenectomy and Roux-en-Y reconstruction. Pathological analysis revealed a large number of gastric NET (grade 1) with a maximum size of 4.5 mm invading the submucosal layer. A single lymph node metastasis was also detected pathologically at station #4d. The postoperative course was uneventful, and serum gastrin normalized postoperatively. At postoperative year 3, the patient has been doing well without any recurrences. CONCLUSIONS: The present case of multiple gastric NET with a single regional lymph node metastasis at year 32 of follow-up was successfully treated with a robotically assisted total gastrectomy.

Bouveret Syndrome simultaneous with an incidental solitary Gastric Neuroendocrine Tumor in a 44-year-old female - A Case Report.

Bouveret Syndrome (BS) is a rare type of gallstone ileus, where a gallstone passes via a cholecystoduodenal fistula and causes gastric outlet obstruction. It comprises 0.3-0.5% of cholelithiasis complications. It primarily affects females with an average incidence age of 74 years. Gastric Neuroendocrine Tumors (G-NETs) make up merely 2% of all forms of gastric neoplasia and are known to be an extremely rare occurrence. Their annual incidence is estimated to be one to two per 1 million individuals, and they comprise 8.7% of all known neuroendocrine neoplasia of the gastrointestinal system. Case presentation: We present the case of a 44-year-old Middle Eastern female who presented to the clinic due to multiple episodes of food containing biliary nonprojectile emesis accompanied by epigastric pain. Preoperative radiological workup revealed a Bezoar blocking the gastric outlet and a G-NET in the mucosal layer of the stomach. Clinical discussion: Surgical intervention consisted of excising the impacted calculus to relieve the existing gastric outlet obstruction simultaneous to performing an uncut Roux-en-Y to treat the G-NET condition. The patient underwent complete recovery. Conclusion: BS is an extremely rare form of gallstone ileus and gastric outlet obstruction. Its clinical presentation is nonspecific and results in misdiagnosis. Additionally, it is rare to occur in our patient's age group. NETs are also profoundly rare forms of neoplasia. To the best of our knowledge, no previous cases of simultaneous BS and G-NET have been documented. Therefore, clinical awareness should be raised to timely implement the necessary therapeutic interventions.

Clinical characteristics and long-term prognosis of type 1 gastric neuroendocrine tumors in a large Japanese national cohort.

OBJECTIVES: Optimal management of type 1 gastric neuroendocrine tumors (T1-GNETs) remains unknown, with few reports on their long-term prognosis. This study investigated the clinical characteristics and long-term prognosis of T1-GNETs. METHODS: We reviewed the medical records of patients diagnosed with T1-GNET during 1991-2019 at 40 institutions in Japan. RESULTS: Among 172 patients, endoscopic resection (ER), endoscopic surveillance, and surgery were performed in 84, 61, and 27, respectively, including 27, 77, and 2 patients with pT1a-M, pT1b-SM, and pT2 tumors, respectively. The median tumor diameter was 5 (range 0.8-55) mm. Four (2.9%) patients had lymph node metastasis (LNM); none had liver metastasis. LNM rates were significantly higher in tumors with lymphovascular invasion (LVI) (15.8%; 3/19) than in those without (1.1%; 1/92) (P = 0.016). For tumors <10 mm, LVI and LNM rates were 18.4% (14/76) and 2.2% (2/90), respectively, which were not significantly different from those of tumors 10-20 mm (LVI 13.3%; 2/15, P = 0.211; and LNM 0%; 0/17, P = 1.0). However, these rates were significantly lower than those of tumors >20 mm (LVI 60%; 3/5, P = 0.021; and LNM 40%; 2/5, P = 0.039). No tumor recurrence or cause-specific death occurred during the median follow-up of 10.1 (1-25) years. The 10-year overall survival rate was 97%. CONCLUSIONS: Type 1 gastric neuroendocrine tumors showed indolent nature and favorable long-term prognoses. LVI could be useful in indicating the need for additional treatments. ER for risk prediction of LNM should be considered for tumors <10 mm and may be feasible for tumors 10-20 mm. TRIAL REGISTRATION: The study protocol was registered in the University Hospital Medical Information Network (UMIN) under the identifier UMIN000029927.

Clinical and pathological profile of gastric neuroendocrine tumors.

Background: Gastric neuroendocrine tumors (G-NETs) are classified into well-differentiated NETs with three grades and poorly differentiated neuroendocrine carcinomas based on morphology and the Ki-67 index. Besides, G-NETs are broadly classified into four types based on clinical and pathophysiological features. Aim: To study clinical and pathological features of different types and grades of G-NET. Materials and Method: All G-NETs, diagnosed from January 2011 to December 2020, were included. Clinical presentation, peritumoral findings, lymph node status, and liver involvement were obtained and correlated with different grades and types of G-NETs. Results: NET was diagnosed in 88 cases. Tumors were graded as I, II, III, and carcinoma in 58, 14, 12, and 4 cases, respectively. Type I NET (49.2%) in the background of chronic atrophic gastritis was the most common type followed by type III (33.3%). Type I tumors were predominantly graded I (91.1%) and limited to the mucosa and submucosa. MEN-1-associated G-NET (type II) was seen in eight cases. All except one type II tumor was associated with ZES syndrome. Remarkably, peritumoral mucosa showed atrophy and intestinal metaplasia in 52.1% and 24.6% cases, respectively. Two cases were associated with adenocarcinoma. Lymph node metastasis was seen in all carcinoma and grade III cases. All carcinoma cases and 58.3% of grade III tumors showed liver metastasis. Conclusion: Biological behavior of G-NET varies with different types and grades of tumor. Typing and grading of G-NET should be done whenever possible to predict the aggressiveness of the tumor.

Aquaporin-4 protein antibody-associated optic neuritis related to neuroendocrine tumor after receiving an inactive COVID-19 vaccine.

Neuromyelitis optica (NMO), also known as Devic's disease, is a rare, autoimmune, and recurrent demyelinating disorder that primarily affects the spinal cord and optic nerve. We report a case with recurrent optic neuritis caused by the paraneoplastic NMO spectrum disorder in the setting of a gastric neuroendocrine tumor 2 weeks after receiving an inactive COVID-19 vaccine.

Pernicious Anemia: The Hematological Presentation of a Multifaceted Disorder Caused by Cobalamin Deficiency.

Pernicious anemia is still a neglected disorder in many medical contexts and is underdiagnosed in many patients. Pernicious anemia is linked to but different from autoimmune gastritis. Pernicious anemia occurs in a later stage of autoimmune atrophic gastritis when gastric intrinsic factor deficiency and consequent vitamin B12 deficiency may occur. The multifaceted nature of pernicious anemia is related to the important role of cobalamin, which, when deficient, may lead to several dysfunctions, and thus, the proteiform clinical presentations of pernicious anemia. Indeed, pernicious anemia may lead to potentially serious long-term complications related to micronutrient deficiencies and their consequences and the development of gastric cancer and type 1 gastric neuroendocrine tumors. When not recognized in a timely manner or when pernicious anemia is diagnosed with delay, these complications may be potentially life-threatening and sometimes irreversible. The current review aimed to focus on epidemiology, pathogenesis, and clinical presentations of pernicious anemia in an attempt to look beyond borders of medical specialties. It aimed to focus on micronutrient deficiencies besides the well-known vitamin B12 deficiency, the diagnostic approach for pernicious anemia, its long-term complications and optimal clinical management, and endoscopic surveillance of patients with pernicious anemia.

Gastric and Duodenal Neuroendocrine Tumor Incidentally Found on Endoscopy During the Evaluation of Iron-Deficiency Anemia.

Neuroendocrine tumors (NET) are a small fraction of overall gastrointestinal (GI) malignancies. Recently the incidence of NETs has increased due to advancements in diagnostic modality. While solid tumors are easily visible on routine endoscopy, identifying endocrine tumors can be difficult, and low incidence and non-specific presentation can be easily missed on upper gastrointestinal endoscopy (UGIE). The management differs based on the type of tumor and location, but the overall prognosis is good. We present a 59-year-old male with multiple NETs throughout the GI tract, diagnosed on repeat esophagogastroduodenoscopy (EGD) with endoscopic ultrasound (EUS) showing multiple gastric folds. A biopsy of multiple nodules was taken to diagnose type I NET with grade 2 differentiation finally. The mucosal nodules were resected with a band ligator, and surveillance endoscopy was recommended.

Study on the risk factors of type 1 gastric neuroendocrine tumor in 123 cases of autoimmune gastritis / 中华消化杂志

Objective:To investigate the risk factors of type 1 gastric neuroendocrine tumor (g-NET) in patients with autoimmune gastritis(AIG).Methods:From September 1, 2016 to February 28, 2022, 123 patients with AIG visited the First Affiliated Hospital of Zhengzhou University were retrospectively enrolled, including 37 cases with type 1 g-NET and 86 cases without type 1g-NET. The clinical data, serological indicators, and endoscopic manifestation of all the patients were analyzed, including the age at the time of AIG diagnosis (hereinafter referred to as the age at diagnosis), levels of gastrin 17 and pepsinogen Ⅰ (PGⅠ), presence or absence of gastric fundus and gastric body polyps, etc. The independent risk factors of type 1 g-NET in AIG patients were analyzed by univariate and multivariate logistic regression. The receiver operating characteristic curve (ROC) was plotted to analyze the optimal cut-off value, sensitivity and specificity of the independent risk factors in predicting type 1 g-NET in AIG patients. Independent sample t test, Mann-Whitney U test and chi-square test were used for statistical analysis. Results:Compared with those of the AIG patients without type 1 g-NET, the age at diagnosis of AIG patients with type 1 g-NET was younger ((57.49±11.16) years old vs. (48.49±10.96) years old), the level of gastrin 17 was higher (200.21 ng/L, 121.85 ng/L to 244.40 ng/L vs. 244.40 ng/L, 182.50 ng/L to 248.02 ng/L), and the proportion of patients with gastric fundus and gastric body polyps was higher(18.6%, 16/86 vs. 56.8%, 21/37), and the differences were statistically significant( t=-4.13, Z=-3.06, χ2=17.90; P<0.001, =0.002 and <0.001). The results of univariate logistic analysis showed that the age at diagnosis ( OR=0.931, 95% confidence interval (95% CI)0.895 to 0.967), gastrin 17( OR=1.012, 95% CI 1.005 to 1.019), PGⅠ( OR=0.974, 95% CI 0.950 to 0.998)and gastric fundus and gastric body polyps( OR=5.742, 95% CI 2.461 to 13.399)were the influencing factors of type 1 g-NET in AIG patients ( P<0.001, =0.001, =0.033 and <0.001). The results of multivariate logistic regression analysis indicated that the age at diagnosis( OR=0.921, 95% CI 0.881 to 0.964), gastrin 17( OR=1.011, 95% CI 1.001 to 1.020), gastric fundus and gastric body polyps( OR=7.696, 95% CI 2.710 to 21.857)were the independent risk factors of type 1 g-NET in AIG patients ( P<0.001, =0.024 and <0.001). The results of ROC analysis demonstrated that the optimal cut-off values for the age at diagnosis and gastrin 17 in predicting type 1 g-NET were 56.50 years old and 206.40 ng/L, respectively; with sensitivity of 83.8% and 70.3%, respectively, and specificity of 54.7% for both ( P<0.001 and=0.003). Conclusion:The age at diagnosis< 56.50 years old, gastrin 17>206.40 ng/L and the presence of gastric fundus and gastric body polyps are independent risk factors of type 1 g-NET in AIG patients.

A Modified T-Stage Classification for Gastric Neuroendocrine Tumors.

BACKGROUND: The eighth edition of the American Joint Committee on Cancer (AJCC) staging manual's TNM staging classification for gastric neuroendocrine tumors has been shown to have poor prognostic discriminability. The aim of present study was to propose a modified T-stage classification, and externally validate its performance in a separate population data registry. METHODS: A modified T-stage classification with tumor size and extent of tumor invasion was generated from the National Cancer Database between 2004 and 2014 (n = 1249). External validation was performed using the Surveillance, Epidemiology, and End Results registry between 1973 and 2013 (n = 539). RESULTS: In the National Cancer Database population, using the AJCC T-stage classification, the 5-y survival rates were 85.7%, 80.8%, 64.5%, and 46.1% in T1, T2, T3, and T4 patients respectively (P < 0.001). These rates were more contrasting with the modified T-stage (mT) classification at 87.0%, 78.2%, 59.0%, and 40.3% respectively (P < 0.001). When patients within each of the AJCC T stages were stratified by mT stages, significant survival heterogeneity was observed within each of the AJCC T2 to T4 stages (P < 0.01). Conversely, when mT stages were stratified by AJCC T stage, no survival difference was observed in any of the mT stages (P > 0.05). The same analyses were performed using Surveillance, Epidemiology, and End Results data, and all the observed results were validated. CONCLUSION: The current AJCC T stage classification categorizes patients into groups with heterogenous prognosis, thus failing to serve as an effective staging tool. A modified T-stage classification demonstrated significantly improved stratification for patients with gastric neuroendocrine tumors.

Endoscopic features and clinical importance of autoimmune gastritis.

Autoimmune gastritis (AIG) is a special type of chronic gastritis characterized by autoimmune disorders caused by cellular immunity, resulting in the destruction of parietal cells and production of antiparietal cell antibodies. Endoscopic findings of AIG are mainly characterized by corpus-dominant advanced atrophy. The antral area is generally considered to have no or mild atrophy; however, there are cases wherein the gastric mucosa is red or faded due to past infection with Helicobacter pylori or bile reflux. Currently, there are no diagnostic criteria for AIG in Japan, and it is important to make a diagnosis based on the presence of gastric autoantibodies and characteristic endoscopic and histological findings. AIG is associated with gastric cancer, neuroendocrine tumors (NETs), and other autoimmune diseases, such as thyroid diseases, anemia, and neurological symptoms due to impaired absorption of iron and vitamin B12 , and thus requires systemic treatment. The significance of diagnosing AIG is to include patients as a high-risk group for the development of gastric cancer and gastric NETs, provide an opportunity to detect autoimmune endocrine diseases, and initiate therapeutic intervention before anemia and neurological symptoms develop. It is important to pay close attention to the occurrence of AIG comorbidities not only at the time of AIG diagnosis but also during follow-up after detection.

CD3+, CD8+, CD4+ and FOXP3+ T Cells in the Immune Microenvironment of Small Bowel Neuroendocrine Tumors.

The role of inflammation in neuroendocrine tumors is poorly known. The purpose of this study was to characterize the densities of CD3+, CD8+, CD4+ and FOXP3+ T cells in small bowel neuroendocrine tumors (SB-NETs), SB-NET lymph node metastases and gastric neuroendocrine tumors (G-NETs) to assess the prognostic role of immune cell infiltrates in SB-NETs. The final cohort included 113 SB-NETs, 75 SB-NET lymph node metastases and 19 G-NETs from two Finnish hospitals. CD3+- and CD8+-based immune cell score (ICS), and other T cell densities were evaluated. Survival analyses of SB-NETs and SB-NET lymph node metastases were performed with the Kaplan-Meier method and Cox regression adjusted for confounders. The primary outcome was disease-specific survival (DSS). No significant difference in DSS was seen between low and high ICS groups in SB-NETs at 5 years (92.6% vs. 87.8%) or 10 years (53.8% vs. 79.4%), p = 0.507, or in SB-NET lymph node metastases at 5 years (88.9% vs. 90.4%) or 10 years (71.1% vs. 59.8%), p = 0.466. Individual densities of the examined T cell types showed no correlation with prognosis either. SB-NETs and lymph node metastases had similar inflammatory cell profiles, whereas in G-NETs CD3+ and CD8+ T cells were particularly more abundant. In SB-NETs, ICS or T cell densities showed no correlation with prognosis.

Case Report: CMV Infection and Same Mechanism-Originated Intestinal Inflammation Compatible With Bowel/Crohn's Disease Is Suggested in ATP4A Mutated-Driven Gastric Neuroendocrine Tumors.

Mutations in the ATP4A proton pump prevent gastric acidification and explain the chronic autoimmune gastritis scenario that conducts the gastric neuroendocrine tumor (gNET) formation. Here, we wanted to investigate the co-occurrence cytomegalovirus (CMV) infection and intestinal inflammation that presented all members of a family affected with gNET and carrying an ATP4A mutation. Intestinal inflammation persisted after CMV eradication and anemia treatment. The inflammation was compatible with a ileitis/Crohn's disease and was originated by the same autoimmune mechanism described in the tumorigenesis of gNETS. The same secondary disease but no the CMV infection was observed in all members affected with gNET and carrying the ATP4A mutation. Our results suggest that the ATP4A malfunction not only explained gNETs but also the co-occurring disease and opportunistic infections, which allowed to link autoimmune pathologies and gNETs in a unique mechanism. Our results open a new window to better understand not only gastric neoplasms formation but the co-occurring autoimmune disorders and the inflammatory mechanism that compose a premalignant scenario for other tumor formation. Our findings are important since contribute to describe the genetic landscape of the Inflammatory Bowel/Crohn's disease and alert clinicians to monitor patients with gastric neoplasms mediated by achlorhydria mechanisms for concomitant secondary pathologies.

Risk factors for lymph node metastasis in gastric neuroendocrine tumor: a retrospective study.

BACKGROUND: Lymph node metastasis (LNM) plays a vital role in the determination of clinical outcomes in patients with gastric neuroendocrine tumor (G-NET). Preoperative identification of LNM is helpful for intraoperative lymphadenectomy. This study aims to investigate risk factors for LNM in patients with G-NET. METHODS: We performed a retrospective study involving 37 patients in non-LNM group and 82 patients in LNM group. Data of demographics, preoperative lab results, clinical-pathological results, surgical management, and postoperative situation were compared between groups. Significant parameters were subsequently entered into logistic regression for further analysis. RESULTS: Patients in LNM group exhibited older age (p = 0.011), lower preoperative albumin (ALB) (p = 0.003), higher carcinoembryonic antigen (CEA) (p = 0.020), higher International normalized ratio (p = 0.034), longer thrombin time (p = 0.018), different tumor location (p = 0.005), higher chromogranin A positive rate (p = 0.045), and higher Ki-67 expression level (p = 0.002). Logistic regression revealed ALB (p = 0.043), CEA (p = 0.032), tumor location (p = 0.013) and Ki-67 (p = 0.041) were independent risk factors for LNM in G-NET patients. CONCLUSIONS: ALB, CEA, tumor location, and Ki-67 expression level correlate with the risk of LNM in patients with G-NET.

Single-incision laparoscopic antrectomy for type I gastric neuroendocrine tumor: a case report.

BACKGROUND: Type I gastric neuroendocrine tumors (GNETs) originate from hyperplasia of enterochromaffin-like (ECL) cells and are commonly detected in patients with chronic atrophic gastritis, including autoimmune gastritis. Typical treatment for type I GNETs comprises simple surveillance and/or endoscopic resection. For alleviation of hypergastrinemia resulting in ECL cell hypertrophy, antrectomy is a treatment option. Type I GNETs mostly have excellent prognosis, and if a surgical approach is chosen, the procedure must be minimally invasive. One such technique for multiple type I GNETs, minimally invasive single-incision laparoscopic antrectomy (SILA), is reported here for the first time. CASE PRESENTATION: We performed SILA on a 46-year-old woman who developed type I GNETs caused by hypergastrinemia due to autoimmune gastritis. A Lap-Protector was inserted in a 3 cm incision at the umbilicus, and set an EZ Access equipped with two 5 mm trocars and one 12 mm trocar. Antrectomy without lymph node dissection was performed using a 5 mm forward-oblique viewing endoscope, a vessel sealing device, and linear staplers, while reconstruction was by Billroth I reconstruction. Side-to-side anastomosis was performed using a 45 mm linear stapler. The stapler entry hole was sutured intracorporeally using barbed suture material. The operation time was 140 min and blood loss was 5 ml. The patient was discharged ten days after surgery without complications. Serum gastrin level decreased to within the normal range on the day after the operation. One year after surgery, esophagogastroduodenoscopy showed pathological disappearance of all lesions of the remnant stomach. CONCLUSIONS: SILA is a minimally-invasive and tolerable technique for treatment of multiple type I GNETs. In this reported case there was good cohesiveness and effectiveness in normalizing gastrin levels and in elimination of remnant gastric lesions.

Gastric neuroendocrine tumor with Helicobacter pylori-associated chronic gastritis.

INTRODUCTION: Development of gastric neuroendocrine neoplasms in subjects infected with Helicobacter pylori is rare and it occurs through pathogenetic mechanisms related to gastrin. PRESENTATION OF CASE: We report a case of gastric neuroendocrine tumor in a patient infected with Helicobacter pylori and normal gastrin levels. He was treated by endoscopic mucosal dissection after eradication of Helicobacter pylori infection. Histologically the tumor was consistent with a grade 2 well differentiated neuroendocrine tumor. It was characterized by the presence of lymphoid aggregates around and inside the neoplasia. DISCUSSION: Helicobacter pylori-associated chronic gastritis can rarely cause the development of gastric neuroendocrine tumors through mechanisms unrelated to gastrin. CONCLUSION: The one related to a chronic Helicobacter pylori infection may be considered a distinct type of gastric neuroendocrine tumor.

Gastric neuroendocrine tumor: A practical literature review.

Gastric neuroendocrine tumors are gastric neoplasms originating from enterochromaffin type cells and are inserted in a larger group, named gastroenteropancreatic neuroendocrine tumors. They are considered rare and variable in terms of their clinical, morphological and functional characteristics and may be indolent or aggressive. They are classified into types I, II and III, according to their pathophysiology, behavior and treatment. Their diagnosis occurs, in most cases, incidentally during upper digestive endoscopies, presenting as simple gastric polyps. Most cases (type I and type II) are related to hypergastrinemia, can be multiple and are treated by endoscopic resection, whenever possible. The use of somatostatin analogs for tumor control may be one of the options for therapy, in addition to total or subtotal gastrectomy for selected cases. Adjuvant chemotherapy is only reserved for poorly differentiated neuroendocrine carcinomas. Although rare, gastric neuroendocrine tumors have an increasing incidence over the years, therefore deserving more comprehensive studies on its adequate treatment. The present study reviews and updates management recommendations for gastric neuroendocrine tumors.

Prognostic nomogram based on the metastatic lymph node ratio for gastric neuroendocrine tumour: SEER database analysis.

OBJECTIVE: The prediction of survival of gastric neuroendocrine tumours (g-NETs) is controversial. Prognostic effects of the metastatic lymph node ratio (LNR) in patients with g-NET were explored, and a nomogram was plotted to predict the survival rates of patients. METHODS: A longitudinal study conducted on the basis of the Surveillance, Epidemiology, and End Results database. The association between LNR and survival were investigated by using Pearson correlation and Cox regression. Overall survival (OS) and cancer-specific survival (CSS) rates were predicted with the help of nomograms. RESULTS: A total of 315 patients with g-NET diagnosed from 2004 to 2015 were included in this study. LNR was discovered to have a negative correlation with OS and CSS (Pearson correlation coefficients: 0.343 (p<0.001) and 0.389 (p<0.001), respectively). The multivariate analyses indicated age, tumour site, differentiation, T staging, M staging, chemotherapy and LNR to be independent prognostic factors for both OS and CSS. Surgery was also a prognostic determinant for CSS (p=0.003). Concordance indices of the nomograms for OS and CSS were higher than those of the TNM classification (0.772 vs 0.730 and 0.807 vs 0.768, respectively). As per the area under the receiver operating characteristic curve, predictive ability of the nomograms for survival of 1, 3 and 5 years was all better than that of TNM classification. CONCLUSIONS: LNR is an independent predictor of g-NETs. The nomograms plotted in this study have a satisfying predictive ability of survival risks and are capable of guiding tailored treatment strategies for patients with g-NET.